Abstract : High speed deposition of soot preform by double flame burner has been studied to realize uniform large soot. After study of gas flow in reaction vessel, the possibility of high speed and stable deposition has been experimentally clarified to realize over 3g/min deposition rate and over 250km continuous drawing ability. Further coating system has been improved to draw practical fibers with dual UV at the speed of 300m/min. These fibers were formed into ribbon and putted into high density 600 fiber cable with promising results. (Author)